ANTHRO FINAL ACTUAL
(44) What were the major components of the human diet before the appearance of agriculture? Which major components of contemporary diets in industrial societies were unavailable or non-existent before the appearance of agriculture (Lecture: evolution & the human diet)
in hunting gathering societies a large portion of food was animal foods- especially true as you get farther from equator hg ate more protein than contemporary americans and more than what is recommended to us- ate less carbs, ate somewhat more fat but usually healthier fats 2/3 of our modern foods are from foods that were previously unavailable Previously unavailable foods: 1. dairy products 2. crereal grains 3. refined sugars 4. refined vegetable oils 5. refined grains today only 40% of our diet comes form food that was previously available
52) Describe how hypotheses from human behavioral ecology have been tested to explain why some human societies have practiced the custom of dowry payments (Lecture: evolutionary perspectives on mate choice).
Dowry can act as female female competition for males females distribute among males based on resources available competition for male with best resources when polygyny is prohibited Polygyny threshold effect causes females to distribute among males by resources or territory If polygyny is culturally prohibited then female female competition for males with most resources This leads to dowry in socially stratified but non polygynous communities
(46) Describe hypotheses generated by evolutionary psychologists regarding human visual perception (Lecture: introduction to evolutionary psychology/evolution of language).
Evolutionary Logic: • monitoring the location andmovment of animals was more important than monitoring location of plants • so- visual perception should be biased toward quickly and accurately detecting changes in the people and animals in a scene • evolutionary novel objects, even dangerous ones like cars, should elicit less attention than people and animals change detection paradigm experiment: show scene then show again with one object removed then keep flipping back and forth - people were more accurate and quicker in detecting if the objects were animals or people -very quickly label these objects
(42) Explain why race is not a valid category for describing human genetic variation (Lecture: modern human variation, pp. 388-393).
Flaws of the Race Concept: 1. the human species can be naturally divided into a small number of distinct races 2. members of different races are genetically different in important ways so knowing a persons race gives you important info about them 3. the differences between races are due to biological heritage. Why Race is not a Valid Category: 1. there are no sharp genetic discontinuities between the so called races 2. the genetic traits used in racial classification are a small subset of the variable human loci 3. most human genetic variation is local 4. racial classification schemes dont represent natural biological categories
(43) What is the evidence that selection has generated genetic variation between human groups? (Lecture: modern human variation, pp. 374-381, 384-388; Homework Ch. 14, Q. 5).
1. Selection that favors different genes in different environments creates and maintains variation among groups - ie. lactose in pastoral groups 2. Genetic Drift creates variation among isolated populations - founder effect- genetic drift caused by expansion of small founding population 3. patterns of genetic variation reflect history of migration and population growth in the human species - as pops expand local pops become genetically isolated from one another and begin to accumulate genetic differences 4. Adaptive differences - ie. larger bodies in colder climates 5. environmental components - ie. lawn example 6. genetic differences - some alleles are more common in certain populations, ie more tall alleles or short alleles
(51) Describe how hypotheses from human behavioral ecology have been tested to explain patterns of polyandrous marriage among the Nyinba? (Lecture: evolutionary perspectives on mate choice)
Predictions: 1. since males fitness is likely influenced by number of cohusbands predicts marriages will more co husbands will be less stable 2. mens satisfaction with marriage linked to age of their wife 3. men who initiate divorce are younger than first wife and older than new wife 4. predict mens reproductive success will be linked to satisfaction with marriage
(40) Explain what is meant by heritability, and be prepared to apply the concept to an example that you haven't seen before (Lecture: modern human variation, pp. 381-388).
HERITABILITY: the fraction of the phenotypic variation in the population that is the result of genetic variation 1. tells you about the sources of variation amongindividuals not relative roles of genes in an environment of development of individual - cake recipe analogy - cake=genes, recipe= evironment - cake and recipe are intertwined 2. A trait's heritability is particular to a specific population at a specific time: a trait's heritability can change as a population changes • 3. A trait's heritability tells you nothing about the sources of phenotypic differences between groups that live in different environments If a phenotypic trait is under strong stabilizing selection, such that there's very little variation in its underlying genes, then it may have fairly low heritability even though we would normally regard the trait as "genetically determined": almost all the variation that the trait does exhibit will be due to environmental variation
(45) Explain why even learned behavioral patterns can be explained as products of natural selection (Lecture: introduction to evolutionary psychology/evolution of language, pp. 65-68, 397-401; Homework Ch. 15, Q. 2 is also relevant)
Learned behaviors are a product of natural selection because not everything is solely determined by genes. Gene expression is largely related to how the environment causes these genes to be expressed. Furthermore natural selection can shape development so that organisms develop different adaptive behaviors in different environments. So some behaviors are a product of natural selection because theya re selected for a particular environment or individual. Evidence also shows that some animals are predisposed to learn some things and not others. Natural selection determines the kinds of problems animals are good at solving and this is how it can also effect learned behaviors. some animals are innately channeled to learning things. furthermore, some behaviors change when in different environments. know that they wont increase fitness in certian environment showing that certain behavioral patters are tied to natural selection
(38) Explain how evidence from comparative genetics (mitochondrial DNA, Y-chromosome genotypes and nuclear DNA) sheds light on the origin of Homo sapiens. Be prepared to write about both (a) comparisons among living human populations and (b) insights from ancient DNA, including DNA from Neandertals and "Denisovans." (Lecture: origin of Homo sapiens, pp. 331-343)
MTDNA is inherited only through maternal line and is not subject to recombination. The only change is through mutation so it is able to be traced back to one individual which helps find the origins of homo sapiens This is similar with the y chromosome. Every y chromosome can be traced back to a single male a)Humans are considerably less variable genetically than chimpanzees. Genetic data indicate that all modern humans are descended from a population of about 12000 reproducing adults. The sequence of human and chimp genomes tell us that there are 9555 human protein coding genes that have a different dna sequence from the homologous gene in chimps There is more variation within populations than between them with regards to genetic variation among humans from Africa, Asia, and Europe - two humans from the same pop are more similar than 2 chimps from same pop - 2 humans from diff pops are more similar than 2 chimps from same pop other great ape species also show more genetic variation than modern humans Humans are less genetically variable than chimpanzees because: 1. mutation introduces ariation at low rate 2. genetic drift eliminates variation 3. rate of loss depends on population size 4. large pops are more variable than small pops 5. human populations may have gone through a bottleneck and then expanded quickly b) Neanderthal and Denisova genomes are more similar to each other than to modern humans but also indiviate that these two hominins had different evolutionary histories. Neanderthals shared a common ancestor after they split from denisova lineage. Ancient genomes indicate that there was a modest amount of interbreeding between neanderthals and denisovans.
(55) Explain how evolutionary social scientists have sought to explain patterns of human violence. (Lecture: evolutionary perspectives on violence).
They don't assume that violence increase perpetrators' reproductive success look at homicide because it is a reliable measure of social conflict- not fitness promoting just easy to monitor not much reporting bias but it taps into strong emotions Homicides among unrelated adults 1. Humans are sexually dimorphic- men are more prone to intra sexual conflict and therefore more likely to kill each other than women, there is greater male male competition than female female competition for mates 2. This is found in all societies 3. Homicide rates are also expected to peak at ages when men are establishing their reputations which is also seen 4. Also unmarried men should be expected to commit more homicides and studies show both divorced and widowed men revert to the same higher homicide rates Age Distribution 1. altercations about status 2. men in early teens and late 20's is where we would think to see this because this is time when people are establishing their reputation Homicide and Kinship • False belief of but don't people frequentyly kill their rleatives o Relatives would mean only genetic relatives o Kin tend to live together which makes conflict more likely o If discussing co residence: ♣ Genetic kin kill each other far less frequently than expected by chance Child Abuse and Homicide • Step parental care is best viewed as a mating effort and therefore children are more at risk of being killed or abused by step parents o Effects of step parenthood on risk of child abuse/ homicide persist after controlling for ♣ Household povrty ♣ Family size ♣ Maternal youth Oddly enough step parents usually spare their own genetic children
(41) Explain how studies of human twins allow researchers to estimate the effects of genetic and environmental differences on variation in phenotypic traits (Lecture: modern human variation, pp. 382-383).
Twin studies allow researchers to look at actual genetics and seeing how they are expressed and therefore effect how individuals look. Monozygotic twins have the same genetic code and therefore should express genes similarly. Researchers also look at environment especially with dizygotic twins to see how the outside environment effects expression of genes. Genetic traits should be more similar in monozygotic twins. Cake Recipe Analogy: the heritability of a trait tells you the source of variation among individuals not about the relative roles of genes and environment in an individuals development. - at every moment in baking a cake both the recipe or genes and the ingredients or environment are involved and intertwined, no way to separate them.
(49) Describe the Westermarck hypothesis for inbreeding avoidance, and one piece of evidence for it in humans. (Lecture: evolutionary perspectives on mate choice, pp. 401-404).
WESTERMARCK: the idea that childhood propinquity stifles desire. He means that people who live in intimate association as small children do not find each other sexually attractive as adults One example is the Taiwanese minor marriage- kids raised together that weren't realte and were supposed to get married later really did not want to have sex later in life.
(53) Describe findings by evolutionary psychologists regarding sex differences (and similarities between the sexes) in human mate choice criteria and attributions of the opposite sex's sexual/romantic intentions (evolutionary perspectives on mate choice; pp. 405-411).
Womens mate choice criteria predited to be related to resources • human infants require extended care • in foraging societies men contribute critical resources for women and children • womens fitness enhanced by male provisioning • females will prefer mates who can and will provide resources for offspring • in societies in which individuals can acquire property and resources, females will prefer wealthy males Male mate prefernces are expected to be based on female fertility • male mating success depends on reproductive success of partner • womens reproductive potential peaks in early adulthood and declines until menopause • this means men are expected to prefer young women who show fertility people generally care most about the personal qualities of their mates women value good financial prospects and ambition more than men do men value good looks more than women do men seek younger partners, women seek older partners women are more likely to seek stable commited relationships
(54) What are the two evolutionary hypotheses proposed to explain the maintenance of personality variation in humans, and what evidence supports each hypothesis? (Lecture: evolution of personality).
• Balancing Selection o Trade offs between the costs and benefits of different levels of the personality traits ♣ Ie a study in britain showed a positive correlation between extraversion and number of sex partners but also a correlation between extraversion and likelihood of being hospitalized due to accident or illness o Therefore trade offs vary ♣ Geographically ♣ Over short time scales ♣ As a function of existing trait frequency • Ie. Village in Senegal- female neuroticism: o Positively correlated with number of offspring produced o In women of lower social status negatively correlated with offspring survival o Total number of surviving offspring highest in women of intermediate neuroticism • Mutation Selection Balance o There is an optimum human personality configuration favored by selection but mutation continuously undermines it ♣ Ie. Genetic and personality data from >8000 finns showed that those who were slightly more inbred were slightly less extraverted and ore neurotic • As youd expect if o High extraversion and low neuroticism are generally fitness enhanving and o Inbreeding depression increases the concentration of deleterious recessive alleles
(50) Describe how hypotheses from human behavioral ecology have been tested to explain mate choice criteria among the Kipsigis (Lecture: evolutionary perspectives on mate choice, pp. 412-414).
• The grooms father is likely to prefer a bride who will provide many grand children • Also find a wife who will do household labor • May also prefer woman whos natal group is further away so that she can dedicate more time to her own family • Plump women received highest bridewealths because seen as having earliest menarche as well as best nutritional status for bearing children. o Overall: ♣ Womens mate choice criteria predicted to be related to resources ♣ Male mate preferences are expected to be based on female fertility